How to Grow Hydroponic Lettuce
Hydroponics, which literally means, "working water," is the
growth of plants without soil. The grower provides the plants with all of the
nutrients they would usually get from the soil though water instead.
Hydroponics can be used on a mass productions scale, or it can easily be scaled
down for use by the home gardener as well. If you are new to hydroponics,
growing hydroponic lettuce is a good place to start. The plants are easy to
work with and forgiving to novice gardeners.
You will need to prepare for starting your hydroponics
garden two weeks in advance of actually planting the lettuce. First, gather
your equipment. You will need a 5-gallon container with a lid. Dark, plastic
containers work best, because the darkness helps keep algae from growing. If
you can only find a clear plastic container, cover it with a dark plastic film
or aluminum foil. You will also need a growing medium. Root cubes, such as
Oasis root cubes, work well for lettuce. Root cubes are pre-formed growth
medium, making them easy to handle. They should have a neutral pH and be
designed for propagation. Of course, you will also need your lettuce seedlings.
Two weeks in advance of the planting, insert the seedlings in the growth cubes,
and keep them in a dish of water.
While your seedlings are in water, you can prepare the lid
of your container for planting. Take plastic planting cones, and trace their
outlines on the lids. Four to six should fit, evenly spaced on a 5 gallon lids;
just try to not get too close to the edge. Cut out the circles you have traced
with the plastic planting cones, and insert the cones into the holes.
Now you can create your water nutrient solution. This is the
most crucial step in hydroponic growing; remember you must supply via water all
the nutrients plants would normally get through the soil. There are many
pre-mixed hydroponics solutions on the market, and one of these should be the
base for your solution. For a 5-gallon drum, take 2 teaspoons of the pre-mixed
hydroponic fertilizer (8-15-36 works well), 2 teaspoons of calcium nitrate, and
1 teaspoon of Epsom salt (magnesium sulfate). Dissolve each of these
ingredients, one at a time, in a cup of water, and then add the water to the
drum. Once you have added your nutrients, fill the drum to near the top with
water.
After your seedlings have been sitting in water for two
weeks, they are ready to add to the planters. First, place your lid over the
drum and secure it in place with duct tape. Then, place the seedlings, inside
the root cubes, into the plastic planting cones, which should already by in the
holes you made in your drum lid. Hydroponic lettuce needs plenty of sunlight;
about equal amounts of direct and indirect sunlight works best.
You will need to keep an eye on the plants for any insects
or worms. If you do see insects, you should remove them by hand. Pesticides are
used in hydroponic gardening, but they are not recommended for growth projects
on such a small scale as this. Also, keep an eye on the water in the drum, make
sure the plants are taking water, and make sure the water level is not getting
too low.
Within 4 to 5 weeks, you should have fully grown lettuce
plants, ready to pick. To pick, simply remove the leaves. Though some kinds of
hydroponic growth mediums can be recycled, root cubes should not be used more
than once.
